1. Field of the Invention
This invention relates to the field of data processing systems. More particularly, this invention relates to the field of malware scanning, such as, for example, scanning for computer viruses, worms, Trojans, banned words etc, within data processing systems.
2. Description of the Prior Art
It is known to provide malware scanners that are able to scan data for the presence of malware such as computer viruses, worms, Trojans, banned words and other undesirable material. One type of malware scanner is resident upon a client computer or a server computer and serves to scan files for malware either on an on-access or an on-demand basis.
A significant source of malware is data downloaded via the internet. The anonymous and unregulated nature of the internet mean that it is relatively easy for a person to distribute malware via the internet, such as to unsuspecting users downloading programs or webpages that contain computer viruses or worms. In order to address this problem it is known to provide malware scanners that operate in conjunction with a computer network firewall such that data being retrieved from the internet through that firewall is scanned for malware. Whilst this is an effective protection, it suffers from the disadvantage that it slows the speed with which data requested by a user from the internet is returned to that user since the data is delayed within the firewall whilst it is scanned. This problem is made worse by the fact that there is an ever increasing number of malware threats, such as known viruses, worms, Trojans etc for which a search needs to be made within the data.